Construction of internalcombustion engines



Oct. 14, 1947. E. P. PAXMAN 2,429,105

CONSTRUCTION OF INTERNAL-COMBUSTION ENGINES Filed Oct. 4, 1943 8 Sheets-Sheet 1 Inventor A ltorneys Oct. 14, 1947. E. P. PAXMAN 2,429,105

CONSTRUCTION OF INTERNALCOMBUSTION ENGINES Filed Oct. 4; 194:: s Sheets-Sheet 2 i r CW 0 a fi a o I a i \M N G o o A a o 0 0 3h bQ F 0 RE a 0 o C 0 (N g Q c g I J g 4 mi};

2 ventor A ttorneys Oct. 14, 1947. p PAXMAN 2,429,105

CONSTRUCTION 6F INTERNAL-COMBUSTION ENGINES Filed Oct. 4, 1943 8 Sheets-Sheet 3 A Home y S Oct. 14, 1947. E. P. PAXMAN 2,429,105

CONSTRUCTION OF INTERNAL-COMBUSTION ENGINES Filed Oct. 4, 1943 8 Sheets-Sheet 4 [no ntor ML UE A ttorneys Oct. 14, 1947. E. P. PAXMAN CONSTRUCTION OF INTERNAL-COMBUSTION ENGINES Filed 001;. 4, 1943 8 Sheets-Sheet 5 [no ntor QSMAJ y L/Q Altomeys @ct. 14, 1947. E. P. PAXMAN CONSTRUCTION OF INTERNAL-COMBUSTION ENGINES Filed 001;. 4, 1943 8 Sheets-Sheet 7 A Home y S Oct. 14, 1947. E. P. PAXMAN 2,429,105

CONSTRUCTION OF INTERNAL-COMBUSTION ENGINES Filed 001;- 4, 1943 8 Sheets-Sheet 8 5 n I ll II I ll Patented Oct. 14, 1947 CONSTRUCTION COMBUSTIO OF INTERNAL- N ENGINES Edward Philip Paxman, ColchestenEngland Application October 4, 1943, Serial No.

In Great Britain July 14, 19421 2 Claims.

This invention relates to internal combustion engines of the kind wherein two banks of cylinders are arranged in mutually inclined positions upon a common crank case, and the object of the invention is to provide improvements in the design of such engines for the purpose of simplifying and expediting manufacture and assembly.

In the production of engines of the kind above indicated it has been a common practice to form each cylinder bank or block as a single casting but owing to the necessity for providing supports for the cylinder liners, mounting for the cam shaft and accessory parts and water cooling spaces, the joint face between cylinder block and crank case is irregular and requires a number of separate and often complex and diflicult operations to machine its co-operating surfaces. Further complex and accurate machining is necessary to secure exact alignment between various components often involving difficult and slow procedure.

The present invention is designed to avoid the difiiculties described in the preceding paragraph and provide an improved arrangement of engine and method of assembling it wherein the manufacture can be carried out on existing small machines and assembly effected by unskilled labour.

The invention consists briefly in constructing an engine comprising two mutually inclined banks of cylinders from a crank case, cylinder units and cylinder head units, the joint faces between the crank case and cylinder units and between cylinder units and cylinder heads units being arranged formachining as plane, uninterrupted surfaces and. the units being arranged to reach the assembly shop as sub-assemblies needing only to be bolted together.

Reference will now be made to the accompanying drawings which illustrate the application of the invention to the construction and assembly of an engine of the Diesel type having two mutually inclined cylinder banks each of six cylinders. In the drawings,

Fig. 1 is a cross sectional elevation of the complete engine,

Fig. 2 is an elevation showing two adjacent cylinder blocks,

Fig. 3 is a plan of Fig. 2.

Fig. 4 is a perspective view of a cylinder head unit,

Fig. 5 is a side elevation of the cam box,

Fig. 6 is a perspective view of the crank case,

Fig. 7 is a cross sectional view of the crank case,

Fig. 8 is a longitudinal sectional elevation of the crank case,

Fig. 9 is a cross sectional view of the free end of the crank case taken on the line A-B of Fig. 8, and

Fig. 10 is view of the drive end of the crank case.

The general arrangement of the engine will be best understood by referring to Fig. 1 which illustrates a cross sectional view through two opposed cylinders. The cylinders indicated at l are formed in blocks each comprising three cylinders, such blocks being illustrated in Figs. 2 and 3 and described in detail hereinafter. The arrangement of cylinders illustrated enables the weight to be lifted for each successive machining operation to be performed, and the size of machine required for theoperation, to be considerably less than under former practice. The base of each cylinder block indicated at 2 is formed by a number of surfaces all lying in one plane which renders the machining of such surfaces to form a joint face to co-operate with a joint face on the crank case, a simple and straightforward operation. The upper surfaces 3 of each cylinder block also lie all in one plane so that a single machining operation forms them of the joint face on to which the co-operating joint face of a cylinder head unit rests. In Fig. 1 the plane of the section has been varied slightly so that the left-hand cylinder head shows an air inlet valve 5 and combustion chamber 6- while the right-hand cylinder head shows an exhaust valve 1.

block and into component parts cylinder head unit is indicated by the lines 8-8 in Fig. 1. Above the lines 88 there are no projecting parts of the cylinder block and below the lines there are no projecting parts of the cylinder head unit.

The cylinder block units are adapted to be mounted upon a crank case, the main body of which consists of a single casting and whose form comprises essentially five longitudinal channelsection girders 9, l0, II, I 2 and I3 connected at intervals, as shown in Fig. 7, by vertical webs it formed with strengthening ribs 15. At the base of the crank case and at each side of the crank shaft l6, reinforcing webs I 1 are provided to take the forces due to the combustion and to the reciprocating and rotating masses of the pistons, rods, bearings and crankshaft.

The top of the crank case provides three joint faces, formed along the upper surfaces of the girders 9, I ll and II, these joint faces comprising a central horizontal face it, and two faces l9 and 20 inclined downwardly and outwardly The joint faces between the cylinder axes of the cylinders in the block which the joint face supports. The component surfaces forma ing each of the three joint faces, l8, l3 and 23 lie in one plane for the purpose of facilitating machining so that without shifting the position of the casting the faces", I! and II can all bemachinedandthebaseofthecastingcanbe bored at 2| to receive the crank shaft bearings. The central horizontal face on the crank case casting forms the support for a cam box 22 3 adapted to be bolted in position, as hereinafter described, and which houses a cam shaft 23 and rockers 24, while its removable cover 25 is adaptwith the three ioint surfaces each lying in one plane, as above described, specific relative pro- 1 portions of the height of the crank case at its outer sides and of the individual cylinders are necessary. For this purpose, the height of each cylinder is reduced but only to such 'an extent that the water cooling space 21 extending substantially to the point of junction at 2 with the crank case provides water cooling for the piston pressure rings at the bottom of the piston stroke. On its outer side, the cylinder block rests upon one of the girder components II or ll of the crank case whose height at the sides is reduced to the minimum consistent with providing adequate strength. The reduction of cylinder length involves the use of acylinder liner 23 which propects a certain distance into the crank case, as shown in'Fig. 1 and which may be reinforced near its outer end by clamping around it a strengthening ring 23 to prevent damage to the liner it struck by the connecting rod so during assembly or dismantling. To enable connecting rods and pistons to be removed, when necessary, crank case openings 3| and doors or covers 32 are'provided in the sides of the crank case. The vertical height of the openings 3|, which must be suiiicient toenahle a piston la connecting rod 33 and big end 33 to be inserted or withdrawn. determines the minimum height between the upper girders l3 and II and their corresponding lower girders l3 and 12 at each side of the crank case and the positions of them. The cylinder blocks l are formed with lugs 34 on theirinner and outer sides, the said lugs being adapted to abut on assembly as shown in Figs. 2

and 3 when they are secured together by nuts and bolts 35. Extending completely along the upper inner edge of each cylinder block is a flange 36 (see Fig. 1) formed with apertures 31 to permit passage of valve push rods as hereinafter described, and both the upper surface of the flange and the main upper surface of the' block are formed with screw-threaded sockets 33 which receive the'lower ends of studs 38 by which the cylinder head .units are secured in their'operative' positions. The upper and lower surfaces of the cylinder blocks, each lying in one plane are indicated by the numerals 3, and 2 respectively in Fig. 2 to correspond with the referencesto these surfaces on Fig. 1.

The cylinder heads 4 are: also formed in blocks of three asshown in Fig. 4 and, as already described, each has the components of its lower face formed in one plane to enable that face to be machined in one operation and without changing its position. These cylinderheads are formed as sub-assemblies each complete with valves 5 7s nents have .ed to support fuel pumps 28 as well as timing chambers t, injectors 42 and other accessory parts in readiness for attachment as complete units by means of the studs 33 to the cylinder blocks.

'In engines of the general character to which the present invention applies it has been the practice to form a cam shaft housing integral with the main casting. Thm practice not only presents the disadvantage of a heavy and unwieldy casting but involves complexities in machining and assembly which add greatly to the time occupied in construction and assembly and necessitate a large proportion of skilled labour to carry out the operations. The arrangement provided bythe present invention enables a clear space to be left between the two inclined cylinder banks (see Fig. 1) whose inner walls are without substantialprojections, the heads of the bolts 43 which fix the cylinder blocks to the crank case being conveniently arranged in the recesses between the cylinders and between apertures 52 (Fig. 6) in the faces I! and 20 through which the cylinder liners 28 project. A clear space is thus formedbetween the cylinder blocks for the disposition of the cam box 22, already described, which seats upon the surface formed by the base of the inverted channel shaped girder 9 extending completely along the top of the crank case. The cam box with the various components mounted upon its cover 25 is placed in position as a complete assembly between the cylinder blocks and is held in position by studs 44 which pass through the cover 25 and bearings for the cam shaft 23 into the girder 9 and are disposed intermediate with studs which serve only to retain the cover 25 in place. This cover with the various components mounted upon it can be removed as one unit to allow access to be gained to the cam shaft 23 without disturbing other parts of the engine. The arrangement also permits of an overhang of the cam box at one end ofthe engine as it only needs aligning at one end where the timing-gear is situated.

A further simplification in manufacture and assembly is effected by avoiding the necessity for accurate alignment between apertures 41 in the vcam box the apertures 31 in the cylinder block flange 36, and passages 48 in the cylinder heads, through which pass the push rods 49 for transmitting the movements of the camshaft rockers 24 to the valve tappet II. The apertures 31 and t1 and passages 48 are made sufficiently large in diameter to allow free passage and angular displacement of the rods 49 and each aperture 41 in the cam box and the aperture 31 above it are connected by a flexible or resilient sleeve 50 constructed and sprung into position in the manner described in my prior Patent No. 2,397,882. The crank shaft 16 is underslung, that is to say, it is supported in bearings disposed below the bored out portions 2i of the crank case webs and its ends are supported in bearings 5| at the free cured in position within the lower recesses 56 (Fig. 'l) of the webs I4 and after assembly of these bearings the lower portion of each web is strengthened by the insertion of long horizontal bolts 51 fixed in position by means of nuts 58.

In manufacturing the engine whose compobeen described in detail, the crank joint faces l920 case, which is the largest and heaviest individual component is first machined to form the joint faces and bored to receive the crank shaft bearings by straight line operations which obviate any necessity for changes of position during machining which would require heavy power driven machinery. The crank shaft comprising a single forging is then placed in position, the bearings 52 and 55 being bolted in place and also the crank case end plates 53 and 54. The cylinder blocks, cylinder head units and cam box which have already been completed as sub-assemblies are then placed in position, the design being such that no one of these assemblies has to be particularly formed to suit the engine in which it is to be used, any one of a, number of available sub-assemblies being capable of application as the completion of the engine structure proceeds. These sub-assemblies being relatively small, due for example, to the cylinder blocks being reduced to groups of three cylinders each, are consequently easy to manipulate and only require to be lifted and then lowered into position onto the joint faces l8, l9 and 20 on the crank case and to be bolted in position thereon. The cylinder blocks are secured in position on the crank case by means of the bolts 43 projecting upwardly through the crank case, joint faces is and 20 and the adjacent cylinder blocks are secured together by the nuts and bolts 35.

The cylinder heads are secured in position upon the cylinder blocks by means of the studs 39 which extend completely through the cylinder heads and whose lower ends engage same in the wall adjacent the water jacket and same in the flanges 36. During the assembly of these components appropriate packing material is interposed between th co-operating joint faces to ensure fluid tight joints being made between the crank case and the joint faces 2 of the cylinder blocks and between the joint faces of the cylinder blocks and the cylinder head units which lie in the planes of the lines 8.

The absence of aligning operations during assembly, besides eliminating skilled labour, greatly reduces engine. The cylinder blocks are free at their outer ends and along their sides. The cam box is free at its sides and top being tied at one end only. This arrangement permits of a certain degree of latitude in the height, length, width and location of the individual cylinder blocks and cylinder heads and the cam box and facilitates the interchangeability already referred to of all cylinder blocks and all cylinder heads.

After assembly of the main components of the engine, as above described, the exhaust manifolds 59 are connected to the inner sides of the cylinder head units and the fuel injectors 42 are connected by pipes 60 to the fuel pumps 26.

Below the crank case is bolted a sump 6| shown in Fig. 1.

I claim:

1. An internal combustion engine comprising a crank case embodying three upper longitudinal channel shaped girders. and vertical ribbed supporting webs connecting said girders transversely at intervals in their length, said girders having formed thereon respectively a central joint the time occupied in the completion of an face and two joint faces inclined laterally from 0 its side edges, each of said joint faces lying wholly in one plane, cylinder block units having upper and lower joint faces each lying wholly in one plane, the lower joint faces of said units being adapted for mounting respectively on said inclined joint faces, the cylinders in said cylinder block units having water jackets, separately formed and inserted liners in the cylinders extending below the water jackets therefor, cylinder head units each having a joint face on its under side lying wholly in one plane and adapted for mounting on the upper joint faces of the respective cylinder block units, and a cam box unit having a joint face on its under side lying wholly in one plane and adapted for mounting on said central joint face, said cylinder block units and cam box unit being constructed as complete subassemblies and adapted to be bolted in position on the inclined and central joint faces respectively on the crank case, and said cylinder head units being constructed as complete sub-assemblies and adapted to be bolted in position on the upper joint faces of the respective cylinder block units.

2. An internal combustion engine of the fuel injection type and embodying two mutually inclined banks of cylinders disposed above a common crank shaft, comprising a crank case, cylinder blocks adapted to be bolted in place on the top of the crank case, fuel injectors and intake and exhaust valves for the cylinders in the blocks, push rods converging from the valves toward the crank case between the cylinder blocks, and an assembly comprising a cam box enclosing a cam shaft-and cooperating rockers and adapted to be EDWARD PHILIP PAXMAN.

' REFERENCES crran The following references are of record in the flle of this patent:

UNITED STATES PATENTS Number Name Date 1,007,842 Belknap Nov. 7, 1911 1,173,105 Fekete Feb.'22, 1916 1,268,522 Williams et a1 June 4, 1918 1,292,165 Vincent Jan. 21, 1919 1,293,712 Church Feb. 11, 1919 1,332,964 Vincent Mar. 9, 1920 1,344,279 Vincent June 22, 1920 1,424,428 Vincent Aug, 1, 1922 1,488,285 Rhoads Mar. 25, 1924 1,416,348 Guy May 16, 1922 1,629,664 Jack May 24, 1927 1,720,510 Chorlton July 9, 1929 1,729,849 Willgoos Oct. 1, 1929 1,803,516 Treiber May 5, 1931 1,900,587 Schutzniedrlg Mar. 7, 1933 2,156,327 Zinner May 2, 1939 FOREIGN PATENTS Number Country Date 130,276 England July 31, 1919 491,084 France 1919 528,666 England 1940 

